A scroll compressor in which stepped portions are provided at arbitrary positions along spiral directions of top and bottom lands of spiral wraps of a stationary scroll and a turning scroll and the heights of the spiral wraps on an outer peripheral side are larger than the heights of the spiral wraps on an inner peripheral side with the stepped portions as boundaries is known in scroll compressors. This scroll compressor is adapted so that the heights of compression chambers in the direction of an axis on the outer peripheral side of spiral wraps are larger than the heights of the compression chambers in the direction of the axis on the inner peripheral side of the spiral wraps and three-dimensional compression can be performed, that is, gas is compressed in both circumferential directions and height directions of the spiral wraps. Accordingly, the performance of the scroll compressor is high and the size and weight of the scroll compressor are reduced.
In this stepped scroll compressor, high top lands, low top lands, high bottom lands, and low bottom lands with the stepped portions of both the scrolls as boundaries are generally formed of flat surfaces having the same height. However, PTL 1 provides a scroll compressor in which a gap, which is formed by the high bottom land and the low top land on the side closer to the inner periphery than the stepped portions, is set to be larger than a gap, which is formed by the low bottom land and the high top land on the side closer to the outer periphery than the stepped portions when both the scrolls mesh with each other so that both the gaps are substantially equal to each other by thermal expansion, in order to avoid the contact between the lands caused by thermal expansion.